Have you ever wondered about wine label descriptions? How can one wine have flavours and aromas of tobacco, mint and chocolate while another has citrus, honeydew melon and pineapple, when both are made from grapes?
You may have asked yourself a similar question while perusing the Chardonnay aisle at your local bottle shop — setting your sights on a bottle with an appealing label and a whimsical blurb that reads like second-rate poetry: zesty orange peel intermingles with a delicate herbaceousness on the nose, while bursts of yellow peach and luscious, ripe guava pirouette across the palate… blah blah blah. These often-convoluted descriptions and tasting notes can leave many of us rolling our eyes and scratching our heads. Luscious guava? Orange peel? Who comes up with this stuff?
But there is some truth buried in these elaborate descriptions… so bear with us.
Naturally we are often asked, are these flavours added to the wine? The simple answer is no. Anything labelled “wine” must, by law, be made from grapes and grapes alone. Aside from approved stabilizing and refining agents, no added extras are allowed— that means no orange peel. So, where exactly do these flavours come from if you can’t add them to wine? The answer comes down the molecular make-up of the wine.
The bulk of what makes up a bottle of wine is water (85%) and alcohol (13%). The remaining two percent is where the magic happens!
Wine flavours occur naturally from primary, secondary, and tertiary sources, however, not every wine will express all three of these categories.
Primary aromas are those distinct flavours and smells derived from the fruit itself. As always, the best wine starts in the vineyard and grapes are an incredibly impressionable and delicate fruit. Grapes absorb subtle flavour characteristics from the wild herbs, flowers and grasses surrounding the vineyards as well as from the soil, air, water, and climate where they grow. This combined with each variety’s unique physiological make up means all grapes have trace amounts of aromatic compounds found within the grape skin cells.
While most winemakers will try to preserve the integrity of the primary grape flavours and aromas, it's fermentation that brings out additional layers of secondary flavours. Fermenting grape juice releases a unique, delicately balanced concoction of phenolics, esters, acids, and other organic molecules that would have otherwise remained hidden. These compounds are the flavours and aromas that tantalise our taste and olfactory receptors and, on the micro-level, are chemically identical to compounds found in other parts of nature.
Which is why when you taste a grape, its primary aromatic compounds are mostly undetectable but when grape juice is fermented these compounds are magnified and more easily perceived by the nose.
So, if you’re smelling orange peel in your wine, you’re really smelling limonene or citral— compounds also found in citrus zest. The “freshly cut grass” aroma commonly associated with a signature sauv blanc comes from aldehydes called hexenal and hexanal, while a guava flavour is often produced by a chemical called 3-mercaptohexyl acetate (we know, this one is a bit of a mouthful—but you get the picture!)
Are you still with us? We know, it’s a lot to wrap your head around, but hang in there.
Oak is another common influence on secondary wine aromas. Oak will tend to impart nutty, toasty, vanilla, and other wood like themes to the final wines, while wines aged in stainless steel will be more youthful and fresh exhibiting more primary fruit flavours.
Tertiary aromas and flavours arise from ageing – almost always in the bottle. Bottle age develops interesting new notes in wines and usually means the wine has evolved in character. For example, the berry notes of a young red wine developing into dried fruit notes like prunes and sultanas.
Decoding the molecular make-up of a wine is just the first step in determining its flavour profile. When wine is swirled and sniffed and tasted, the alcohol helps lighter than air compounds reach your nose to be interpreted. Our noses will all process these aroma compounds differently based on memory banks of smells built up over a lifetime.
One of our favourite things about wine is that each individual will have their own unique experience. Your genetics and environment can influence what you taste and how intensely you taste it; perceptions and interpretations of the same drop can vary tremendously from palate to palate. There is no right or wrong answer when identifying flavours and aromas in wine – only your answer! It’s one of the things that makes drinking wine so much fun and a skill that can only be developed by practice. So, trust your instincts and have fun with the process!